Step by step method

1. Preheat oven to 190°C.
2. Grease several baking trays and/or line them with baking paper.
3. Combine flour, baking soda, baking powder and salt in a medium bowl and set aside.
4. In a separate bowl, beat the Stork Bake margarine with the sugars using an electric mixer or wooden spoon for about 5 minutes (until light and fluffy).
5. Beat in egg and vanilla, scraping the sides occasionally.
6. Gradually beat in flour mixture until blended.
7. Stir in the dark and white chocolate chips.
8. Spoon the dough onto the baking trays using a tablespoon or an ice cream scoop. Leave at least 2 inches between each cookie so that they have room to expand.
9. Bake for 10 minutes or until golden.
10. Let stand for 2 minutes on a wire rack; remove from trays and cool completely.
11. Melt the chocolate chips in two separate bowls in a microwave on low power. Drizzle the melted dark chocolate over the cookies followed by the melted white chocolate. Leave to set before serving.